.btn-system {
    background: #3a3a3a; /* For browsers that do not support gradients */
    background: -webkit-linear-gradient(#464646, #363636); /* For Safari 5.1 to 6.0 */
    background: -o-linear-gradient(#464646, #363636); /* For Opera 11.1 to 12.0 */
    background: -moz-linear-gradient(#464646, #363636); /* For Firefox 3.6 to 15 */
    background: linear-gradient(#464646, #363636); /* Standard syntax */
    border: none;
    color: #eeeeee;
    transition: background 0.5s;
}
.btn-system:hover {
    color: #eeeeee;
} 
.btn-system:active, 
.btn-system:default, 
.btn-system:after, 
.btn-system:before, 
.btn-system:focus, 
.btn-system:disabled {
    background: #333333; /* For browsers that do not support gradients */
    background: -webkit-linear-gradient(#333333, #363636); /* For Safari 5.1 to 6.0 */
    background: -o-linear-gradient(#333333, #363636); /* For Opera 11.1 to 12.0 */
    background: -moz-linear-gradient(#333333, #363636); /* For Firefox 3.6 to 15 */
    background: linear-gradient(#333333, #363636); /* Standard syntax */
    border: none;
    color: #eeeeee;
    transition: background 0.5s;
}
.alert-system {
    background: #3a3a3a; /* For browsers that do not support gradients */
    background: -webkit-linear-gradient(left,rgba(255,0,0,0),rgba(0,0,0,1)); /*Safari 5.1-6*/
    background: -o-linear-gradient(right,rgba(255,0,0,0),rgba(0,0,0,1)); /*Opera 11.1-12*/
    background: -moz-linear-gradient(right,rgba(255,0,0,0),rgba(0,0,0,1)); /*Fx 3.6-15*/
    background: linear-gradient(to right, rgba(255,0,0,0), rgba(0,0,0,1)); /*Standard*/
    border: none;
    color: #eeeeee;
}